EPA 608 Evacuation Levels: The Required Vacuum by Appliance

What an evacuation level is

Section 608 doesn't ask you to get every last molecule out. It sets how far you must pull an appliance down, with certified recovery equipment, before you open it for service or dispose of it: the required levels of evacuation in Table 1 of 40 CFR 82.156. The numbers are inches of mercury (inHg) vacuum, measured from standard atmospheric pressure; 0 means 0 psig.

Step 1: find the pressure class

The table sorts appliances by the refrigerant they use, by its liquid saturation pressure at 104°F (40 CFR 82.152):

Swipe the table sideways to see every column.

The trap: R-134a is medium-pressure, not high-pressure, and R-410A is high-pressure like R-22, even though it runs at much higher pressures than R-22.

Step 2: read Table 1

Then look at the charge (the appliance, or the isolated component you're opening, under or over 200 lbs) and at when your recovery or recycling equipment was made:

Swipe the table sideways to see every column.

Worked examples

• A 12-lb R-410A heat pump: high-pressure, under 200 lbs, so 0 psig with any recovery machine.
• A supermarket rack with 300 lbs of R-22 and a recovery machine from 2015: high-pressure, 200 lbs or more, so 10 inHg vacuum.
• A 250-lb R-134a system: medium-pressure, 200 lbs or more, so 15 inHg vacuum.
• An R-123 centrifugal chiller: low-pressure, so 25 mm Hg absolute whatever the equipment's age. That's about 29 inHg vacuum, or 25,000 microns; read it on an absolute pressure gauge, not a compound gauge.

Small appliances use percentages

Small appliances (factory-sealed with 5 lbs or less) have their own rule in 82.156(b). With recovery equipment made on or after November 15, 1993, recover 90% of the charge if the appliance compressor runs and 80% if it doesn't. With older equipment, 80% either way. Or pull the appliance down to 4 inHg vacuum. Weighing what you recovered against the nameplate charge shows where you stand.

When you don't have to reach Table 1

• Repairs that aren't major. A major repair removes the compressor, condenser, evaporator or an auxiliary heat exchanger coil. For anything less, when the appliance won't be evacuated to the atmosphere afterward, very high-, high- and medium-pressure appliances only need to be evacuated to 0 psig, and a low-pressure appliance is pressurized to 0 psig before it is opened, so it doesn't pull in air.
• Leaks. If leaks make the Table 1 level impossible, isolate the leaking parts from the rest where you can. Non-leaking parts still go to the Table 1 level; leaking parts go as low as you can get without contaminating the refrigerant, and never higher than 0 psig.

Disposal uses the same numbers

Before an appliance is scrapped, its refrigerant must be recovered to the same levels: Table 1 for larger appliances, the 80% or 90% rule (or 4 inHg) for small ones. For small appliances, the last person in the disposal chain, such as the scrap recycler, must recover what's left or keep a signed statement that it was already recovered.

One more limit: system-dependent equipment

Recovery equipment that relies on the appliance's own compressor or pressure may only be used on appliances with a full charge of 15 lbs or less, unless it is a pump-out unit permanently attached to the appliance, as on many large chillers.

How the exam asks it

Expect scenario questions: a refrigerant, a charge size and an equipment date, and you pick the level. Learn the pressure classes first, then the table rows, then the exceptions. The Type II questions lean on the high- and medium-pressure rows; Type III on 25 mm Hg; Type I on the percentages. See which certification covers what in Type I vs II vs III.

The EPA 608 Exam Prep app drills these scenarios across Type I, II and III, with the explanation after every answer.